The G9 quartz halogen bulb could have ionisation as the filament ruptured, causing the bulb to explode, and so they always had glass shrouds over the bulb so if they failed, white-hot quartz does not land on the floor. As we moved to LED, we do not need the covers, but not to use them changes the look of the lamp.
So the small Philips LED allows the use of the covers, but with an electronic switch, without a neutral or battery, they would flash, and flicker, the larger of the two bulbs, the covers will not fit, but puts out a lot more light, and the smoothing capacitor inside is nearly as big as the other bulb. Unfortunately the larger lamps does not comply with British regulations, it does not have watts or lumen marked on the bulb, so can only be bought on the internet.
I fitted 5 and one failed sent for 4 spares, but opened up the failed bulb to see what was in it. Very simple, and found a dry joint, so easy to fix, so bulb went back into service, this was 4 years ago, all 5 still running, 4 spares still in their boxes.
Today I use Tapo smart light switches, which do not need a neutral but have a battery in them, so there is no problem with the G9 bulbs.
But my G9 are not dimmable, I am sure you can get versions that are, but the old quartz halogen bulb would have a reduced life if dimmed, and since G9 was originally designed for quartz halogen bulbs, no reason the replacements should dim.
Bulbs have in general moved on. The lumen per watt just 5 years ago with LED was often down to 75, but today we are seeing over a 100 lumen per watt, but the smaller the bulb, the worse they are lumen per watt wise. Also, any smart bulb must use power for the smart bit, even if not much, and LED bulbs tend to shine away from the base, so bulbs with base at bottom, with white ceiling above, tend to do better to a bulb with base at the top, shining down, filament bulbs do give a better spread of light, but we often have a trade-off, what the fitting looks like, to how well it works. In the main I am now using candle E14 bulbs, because they look nice, not because they are good bulbs.
My living room chandelier has 8 x E14 (SES) bulbs, not really bright enough, so we also use up-lighters, and cabinet display lights, these are a better style
but 470 lumen is too low, these
better, but for 8 that's £30.32 which is getting expensive, and non-dimmable. I look at Screwfix as easy to compare bulbs, not saying get from screwfix, but it seems most SES candle bulbs are 470 lumen, the watts can vary 2.9 as shown to 5 watt, but the light output the same.
I would have liked B22d or E27 bulbs, but could not find a chandelier I liked that used those bulbs.
Not sure what you want or have? Are you still using G9 bulbs, and is it two-way or two gang. Personally I would retain wall lamps if I had them, or at least fit a back box and blanking plate so you can return to using them.
I have a small problem using up-lighters, and cabinet displays as want to turn them all off when leaving the room, I use smart socket adaptors and smart light switches, so one command hey google turn off living room turns off all lamps. Turning them on is OK, it is last thing at night going around turning them all off which is a pain.
Also had a problem, falling asleep in the chair, then wakening up in total darkness, hey google turn on living room main lights helps with that, but I also have them set to auto switch on half an hour before dusk. Additionally set to turn off at dawn, in case I forget.
